He’s putting together plans to top off the northernmost piece of his West Side project with a new curved condominium building at 72nd Street, while also working on a new master plan to turn the southernmost commercial portion of the site, at 61st Street, into several more apartment buildings.

Skidmore Owings Merrill is now taking another look at the section on Trump’s behalf. Skidmore planned the original Riverside South project on the Hudson Railyards and helped Columbia University lay out the four-block commercial piece as a Business School and performing arts campus annex.Trump and his Hong Kong-based partners will have to take any development plan for the southern Trump Place site through rezoning and the city’s land use review process.

“We’re designing a fantastic, residential development on that site,” Trump confirmed. “It’s zoned now for commercial and it’s very early in the process, but we will be going for that [zoning] fairly soon.”

Meanwhile, at the northernmost piece of the West Side site, HRH Construction has already begun working on an unusual 35-story tower designed by Costas Kondylis that will eventually contain 180 condominium units.

To its south is the tallest building on the site, a 50-story condo that is topped by a round crown. Another condo and three rental buildings already line Riverside Boulevard.

“We’re doing a building which is going to be really very beautiful, and very luxurious,” Trump said. “It’s going to have a gentle curve and will look up and down Riverside Park and the Hudson River to the George Washington Bridge.”

Trump compared the design to the curved glass façade on the 17 State St. office building downtown, overlooking New York Harbor.

That building gives a sense of what the new Trump condo will look like – just move it uptown, add lots of limestone and spin it around.

As for Trump’s most recent multimillion-dollar commercial venture – a McDonald’s ad filmed in his own offices, overlooking Central Park – Trump laughs, “Not bad for an afternoon.”

If you watch the ad carefully, you might also glimpse of a small rendering of the first few Trump Place buildings.

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Artist Pat Steir has inked a 10-year deal for 5,200-square-feet on the 12th floor of the Starrett-Lehigh Building at 601 West 26th St. that is still home to Martha Stewart’s kingdom.

In-house agents Rob Kurtz and Peter Thorsen repped the building owners in the deal that had an asking rent of $25 a foot.

Roxanne Betesh of Sinvin Realty brought in the artist who has flung, poured, and dripped enough paint in a Jackson Pollack-like manner to get her work added to small galleries like MOMA, the Guggenheim, the Whitney and Metropolitan Museum. Another painting hangs in the Battery Park City’s Embassy Suites Hotel collection.